The twin my baby will never know

There is a folder in my bedroom drawer that I am keeping for posterity. It contains all my old maternity notes – fetal scans, blood pressure readings, even (somewhat unnecessarily, so my husband tells me) pregnancy-related urine test results. I am, admittedly, a hoarder.

My daughter Adriana is now six months old. I know I should ditch the superfluous test results but I plan to keep Adriana’s scans to show her when she’s older. I’ve also kept the scans of our five-year-old son Alex and he often gazes at them, marvelling that he was once so tiny.

They’re hugely important to me, these very first grainy outlines of my children. The 12-week scan in particular, heralded the beginning of new life. But there are times that the scans of Adriana can cause me to become a little maudlin, because there were meant to be two babies: and on the scan I can clearly see Adriana’s tiny, dead twin.

I cannot compare my experience to the heartache of a stillbirth or a loss late in pregnancy. Adriana’s twin died early, so early, in fact, that some might argue that this loss barely counts. Had I been pregnant before the modern age of ultrasound, I’d never have known I was carrying twins at all.

What happened in my case is called Vanishing Twin Syndrome (VTS), where a pregnancy starts off with twins but one then dies and usually disappears, absorbed back into the mother’s body.

At my 12-week scan in April last year, I saw the baby – now my daughter Adriana – kicking away. Then the sonographer paused.

“There are two,” she said.

Then she added quietly: “Were two.”

Twin two was there, a third smaller than Adriana, completely formed, curled up in its own little sac. Twin two had died at around eight weeks’ gestation, I was told. Yet four weeks on, at the 12-week scan, it was still there.

After the shock, I was full of questions. How would the dead twin come out? Would I miscarry it? What about the surviving twin? Was it at risk?

The sonographer explained that normally the dead twin doesn’t miscarry in the usual sense; it is absorbed back into the body. It vanishes – hence the name.

Saddened as well as shocked, I spent the next few weeks searching Google. I was horrified to read that VTS might pose a slightly increased risk of danger to the second twin; that it could indicate a higher risk of cerebral palsy. Instead of wandering about in a joyful, pregnant haze, I became an obsessive worry wart. I didn’t even dare buy baby clothes.

Thankfully, my 20-week scan showed that the surviving twin was growing well. But again, I found myself searching the screen for the shadowy outline of the dead twin.

“It’s still there,” the sonographer said, pointing out a faint smudge.

She told us it was getting smaller; at another scan it probably wouldn’t be there at all. It felt very strange: one twin was growing, the other not.

It made me wonder: scans may have enormous benefits, but do they also have a downside? Greater technology means greater awareness. But ignorance can sometimes be bliss.

Joe Aquilina, consultant obstetrician and gynaecologist at St Bartholomew’s and the Royal London Hospital, says that VTS has always occurred – we are simply more aware of it now, thanks to the development of ultrasound in the Eighties. An early VTS may be due to a chromosomal abnormality, or it may be due to one twin taking more of the mother’s blood, where there is a shared placenta. A later VTS may be associated with brain defects such as cerebral palsy.

Knowing when the twin died is important, he says, as a later date can have implications for the timing of labour.

He adds: “If we are talking about a loss early on – say, under eight weeks – then it probably is a case of ignorance is bliss and better for a woman not to know. But when the demise of one twin is later, say at between 12 and 16 weeks, it can indicate a problem in the surviving twin, and it can also lead to premature labour.”

Before ultrasound, a mother would not even have known she’d lost a twin; although sometimes, if a twin had died later on in pregnancy, there would be a tell-tale sign, even at birth. Midwives would sometimes find evidence of a tiny, dead twin attached to the placenta – forever frozen in arrested development. It is known as fetus papyraceus. The midwife would dispose of the afterbirth along with the remains of the dead twin – perhaps with a silent nod to a fellow nurse or helper. Mothers didn’t need to know.

Dr Peter Pharoah, emeritus professor of public health at Liverpool University, is an expert in VTS. He agrees with Aquilina that the risk of complications for the remaining pregnancy depend on the stage at which the twin dies, but adds: “It is also important to know if it is from a single egg that has split, or two separate eggs. If it is two separate eggs, then any abnormality or problem with the dead twin will probably not affect the other. If the twins are a result of one egg splitting, there may be problems.

“It also depends on whether the twins share a placenta or not. This is because if one twin takes more of the blood flow, it can cause problems that could damage one or both of them, affecting organs like the heart, kidneys or intestines.”

Dr Pharoah adds: “In early Vanishing Twin Syndrome, before eight weeks it might mean that organs such as the heart can be damaged in the surviving twin if they were sharing a placenta. In later cases, from 12 weeks onwards, the brain is rapidly developing and there can be a danger of brain damage or cerebral palsy.”

In his research, Dr Pharoah found that, where twins died in the later stages of pregnancy, the prevalence of cerebral palsy in the survivor was more than 50 times higher than normal.

So how common is VTS? “It’s impossible to know,” he says. “Particularly as, when a dead twin is seen on a scan or if a fetus papyraceus is found in the placenta, it is not recorded. I believe it should be recorded as a death, even if it died before 24 weeks. It’s important to register this because it can have important implications for the surviving twin.”

He concedes, however, that a scan revealing a vanishing twin can cause great – sometimes unnecessary – worry for pregnant women.

“It’s important that we discuss Vanishing Twin Syndrome,” says Dr Pharoah. “But in very early pregnancy, a scan showing this can sometimes be raising a worry that doesn’t need to be there.”

I might have spent my own pregnancy worrying, but I had a happy ending – a bouncing, healthy baby girl. Still, there was a strange mixture of grief and joy when my baby was born – joy that she had made it and sadness that she would have had a brother or sister that she would now never know.

I do occasionally wonder whether Adriana “misses” her twin at some subconscious level. Will I ever tell her that she began life as a twin?